The Cobia (Rachycentron canadum), Kobia, Kingfish or Bullfish is a species of marine fish from the group of spiny mackerel relatives (Carangiformes). It lives in pelagic open water in tropical and subtropical areas of the Atlantic and Indo-Pacific, is up to two meters long and weighs 70 kg.
The Cobia reaches a maximum length of 2 m and a maximum weight of 78 kg. He has an elongated, spindle-shaped body and a broad, flattened head. The eyes are small and the lower jaw protrudes slightly beyond the upper jaw. Fibroid teeth line the jaw, tongue and palate. The body of the fish is smooth with small scales. It has a dark brown color and is white on the belly with two dark brown horizontal stripes on the flanks. The stripes appear more prominent when spawning as they become darker and the background color becomes lighter.
When diving in the Samui archipelago, we may well meet Cobias. usually when a whale shark is nearby.